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输出：true
解释：
前 3 位顾客那里，我们按顺序收取 3 张 5 美元的钞票。
第 4 位顾客那里，我们收取一张 10 美元的钞票，并返还 5 美元。
第 5 位顾客那里，我们找还一张 10 美元的钞票和一张 5 美元的钞票。
由于所有客户都得到了正确的找零，所以我们输出 true。
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br></div></div><p><strong>示例 2：</strong></p> <div class="language- line-numbers-mode"><pre class="language-text"><code>输入：bills = [5,5,10,10,20]
输出：false
解释：
前 2 位顾客那里，我们按顺序收取 2 张 5 美元的钞票。
对于接下来的 2 位顾客，我们收取一张 10 美元的钞票，然后返还 5 美元。
对于最后一位顾客，我们无法退回 15 美元，因为我们现在只有两张 10 美元的钞票。
由于不是每位顾客都得到了正确的找零，所以答案是 false。
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br></div></div><p><strong>提示：</strong></p> <ul><li><code>1 &lt;= bills.length &lt;= 105</code></li> <li><code>bills[i]</code> 不是 <code>5</code> 就是 <code>10</code> 或是 <code>20</code></li></ul> <h5 id="解题思路"><a href="#解题思路" class="header-anchor">#</a> 解题思路</h5> <div class="language-js line-numbers-mode"><pre class="language-js"><code><span class="token number">1.</span> 考虑局部的最优达到全局的最优
<span class="token number">2.</span> 这题可以用贪心是因为决策具有包容性
	<span class="token number">20</span> <span class="token number">10</span> <span class="token number">5</span> ，用这些找零
    <span class="token number">10</span> 找零 相当于 <span class="token number">2</span><span class="token operator">*</span><span class="token number">5</span> 找零
    <span class="token number">20</span> 找零 相当于 <span class="token number">10</span><span class="token operator">*</span><span class="token number">2</span> 找零 <span class="token number">10</span><span class="token operator">*</span><span class="token number">1</span> <span class="token number">2</span><span class="token operator">*</span><span class="token number">5</span> 找零<span class="token operator">...</span><span class="token punctuation">.</span>
    
    也就是顺序，不管前后顺序，可以走到一个相同的结果
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br></div></div><h5 id="完整代码"><a href="#完整代码" class="header-anchor">#</a> 完整代码</h5> <div class="language-js line-numbers-mode"><pre class="language-js"><code><span class="token comment">/**
 * @param {number[]} bills
 * @return {boolean}
 */</span>
<span class="token keyword">var</span> <span class="token function-variable function">lemonadeChange</span> <span class="token operator">=</span> <span class="token keyword">function</span><span class="token punctuation">(</span><span class="token parameter">bills</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>

    <span class="token keyword">let</span> myBills<span class="token operator">=</span><span class="token punctuation">{</span>
        <span class="token number">5</span><span class="token operator">:</span><span class="token number">0</span><span class="token punctuation">,</span>
        <span class="token number">10</span><span class="token operator">:</span><span class="token number">0</span><span class="token punctuation">,</span>
        <span class="token number">20</span><span class="token operator">:</span><span class="token number">0</span>
    <span class="token punctuation">}</span>

    <span class="token keyword">for</span><span class="token punctuation">(</span><span class="token keyword">let</span> i<span class="token operator">=</span><span class="token number">0</span><span class="token punctuation">;</span>i<span class="token operator">&lt;</span>bills<span class="token punctuation">.</span>length<span class="token punctuation">;</span>i<span class="token operator">++</span><span class="token punctuation">)</span><span class="token punctuation">{</span>
        
        <span class="token keyword">let</span> rtn<span class="token operator">=</span>bills<span class="token punctuation">[</span>i<span class="token punctuation">]</span><span class="token operator">-</span><span class="token number">5</span>
        <span class="token keyword">if</span><span class="token punctuation">(</span>rtn<span class="token operator">!==</span><span class="token number">0</span><span class="token punctuation">)</span><span class="token punctuation">{</span>
            <span class="token comment">// 开始找零，每次找最大的</span>
            
            <span class="token keyword">while</span><span class="token punctuation">(</span>rtn<span class="token operator">-</span><span class="token number">10</span><span class="token operator">&gt;=</span><span class="token number">0</span><span class="token operator">&amp;&amp;</span>myBills<span class="token punctuation">[</span><span class="token number">10</span><span class="token punctuation">]</span><span class="token operator">&gt;</span><span class="token number">0</span><span class="token punctuation">)</span><span class="token punctuation">{</span>
                myBills<span class="token punctuation">[</span><span class="token number">10</span><span class="token punctuation">]</span><span class="token operator">--</span>
                rtn<span class="token operator">=</span>rtn<span class="token operator">-</span><span class="token number">10</span>
            <span class="token punctuation">}</span>

            <span class="token keyword">while</span><span class="token punctuation">(</span>rtn<span class="token operator">-</span><span class="token number">5</span><span class="token operator">&gt;=</span><span class="token number">0</span><span class="token operator">&amp;&amp;</span>myBills<span class="token punctuation">[</span><span class="token number">5</span><span class="token punctuation">]</span><span class="token operator">&gt;</span><span class="token number">0</span><span class="token punctuation">)</span><span class="token punctuation">{</span>
                myBills<span class="token punctuation">[</span><span class="token number">5</span><span class="token punctuation">]</span><span class="token operator">--</span>
                rtn<span class="token operator">=</span>rtn<span class="token operator">-</span><span class="token number">5</span>
            <span class="token punctuation">}</span>
            
            <span class="token keyword">if</span><span class="token punctuation">(</span>rtn<span class="token operator">&gt;</span><span class="token number">0</span><span class="token punctuation">)</span><span class="token punctuation">{</span>
                <span class="token keyword">return</span> <span class="token boolean">false</span>
            <span class="token punctuation">}</span>
        <span class="token punctuation">}</span>
        myBills<span class="token punctuation">[</span>bills<span class="token punctuation">[</span>i<span class="token punctuation">]</span><span class="token punctuation">]</span><span class="token operator">++</span>
    <span class="token punctuation">}</span>

    <span class="token keyword">return</span> <span class="token boolean">true</span>

<span class="token punctuation">}</span><span class="token punctuation">;</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br><span class="line-number">15</span><br><span class="line-number">16</span><br><span class="line-number">17</span><br><span class="line-number">18</span><br><span class="line-number">19</span><br><span class="line-number">20</span><br><span class="line-number">21</span><br><span class="line-number">22</span><br><span class="line-number">23</span><br><span class="line-number">24</span><br><span class="line-number">25</span><br><span class="line-number">26</span><br><span class="line-number">27</span><br><span class="line-number">28</span><br><span class="line-number">29</span><br><span class="line-number">30</span><br><span class="line-number">31</span><br><span class="line-number">32</span><br><span class="line-number">33</span><br><span class="line-number">34</span><br><span class="line-number">35</span><br><span class="line-number">36</span><br><span class="line-number">37</span><br><span class="line-number">38</span><br></div></div><h4 id="_45-跳跃游戏-ii-扩展的贪心模板"><a href="#_45-跳跃游戏-ii-扩展的贪心模板" class="header-anchor">#</a> <a href="https://leetcode.cn/problems/jump-game-ii/" target="_blank" rel="noopener noreferrer">45. 跳跃游戏 II(扩展的贪心模板)<span><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" x="0px" y="0px" viewBox="0 0 100 100" width="15" height="15" class="icon outbound"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path> <polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg> <span class="sr-only">(opens new window)</span></span></a></h4> <p>给你一个非负整数数组 <code>nums</code> ，你最初位于数组的第一个位置。</p> <p>数组中的每个元素代表你在该位置可以跳跃的最大长度。</p> <p>你的目标是使用最少的跳跃次数到达数组的最后一个位置。</p> <p>假设你总是可以到达数组的最后一个位置。</p> <p><strong>示例 1:</strong></p> <div class="language- line-numbers-mode"><pre class="language-text"><code>输入: nums = [2,3,1,1,4]
输出: 2
解释: 跳到最后一个位置的最小跳跃数是 2。
     从下标为 0 跳到下标为 1 的位置，跳 1 步，然后跳 3 步到达数组的最后一个位置。
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br></div></div><p><strong>示例 2:</strong></p> <div class="language- line-numbers-mode"><pre class="language-text"><code>输入: nums = [2,3,0,1,4]
输出: 2
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br></div></div><p><strong>提示:</strong></p> <ul><li><code>1 &lt;= nums.length &lt;= 104</code></li> <li><code>0 &lt;= nums[i] &lt;= 1000</code></li></ul> <h5 id="解题思路-2"><a href="#解题思路-2" class="header-anchor">#</a> 解题思路</h5> <div class="language-js line-numbers-mode"><pre class="language-js"><code><span class="token number">1.</span>  预言家
<span class="token number">2.</span> 我们不仅仅走一步，我们多看一步，为了达到更好的结果
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br></div></div><h5 id="完整代码-2"><a href="#完整代码-2" class="header-anchor">#</a> 完整代码</h5> <div class="language-js line-numbers-mode"><pre class="language-js"><code><span class="token comment">/**
 * @param {number[]} nums
 * @return {number}
 */</span>
<span class="token keyword">var</span> <span class="token function-variable function">jump</span> <span class="token operator">=</span> <span class="token keyword">function</span><span class="token punctuation">(</span><span class="token parameter">nums</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>

    <span class="token comment">// 当前位置</span>
    <span class="token keyword">let</span> now<span class="token operator">=</span><span class="token number">0</span>
    <span class="token comment">// 开始跳跃的最远位置</span>
    

    <span class="token comment">// 尝试now+1 .... maxLength</span>
    <span class="token comment">// 跳到时，判断当前的pos再次跳到哪里，选取能跳到最远的</span>
    <span class="token keyword">let</span> res<span class="token operator">=</span><span class="token number">0</span>

    <span class="token keyword">while</span><span class="token punctuation">(</span>now<span class="token operator">&lt;</span>nums<span class="token punctuation">.</span>length<span class="token operator">-</span><span class="token number">1</span><span class="token punctuation">)</span><span class="token punctuation">{</span>
        <span class="token keyword">let</span> maxLength<span class="token operator">=</span>now<span class="token operator">+</span>nums<span class="token punctuation">[</span>now<span class="token punctuation">]</span>
        res<span class="token operator">++</span>
        <span class="token keyword">if</span><span class="token punctuation">(</span>maxLength<span class="token operator">&gt;=</span><span class="token punctuation">(</span>nums<span class="token punctuation">.</span>length<span class="token operator">-</span><span class="token number">1</span><span class="token punctuation">)</span><span class="token punctuation">)</span> <span class="token keyword">break</span>
        <span class="token keyword">let</span> max<span class="token operator">=</span><span class="token operator">-</span><span class="token number">1</span>
        
        <span class="token comment">// 判断跳到第一位置，看能从第一个位置跳到第二个位置最远的</span>
        <span class="token keyword">for</span><span class="token punctuation">(</span><span class="token keyword">let</span> pos<span class="token operator">=</span>now<span class="token operator">+</span><span class="token number">1</span><span class="token punctuation">;</span>pos<span class="token operator">&lt;=</span>maxLength<span class="token punctuation">;</span>pos<span class="token operator">++</span><span class="token punctuation">)</span><span class="token punctuation">{</span>

            <span class="token keyword">let</span> distance<span class="token operator">=</span>pos<span class="token operator">+</span>nums<span class="token punctuation">[</span>pos<span class="token punctuation">]</span>
            <span class="token keyword">if</span><span class="token punctuation">(</span>distance<span class="token operator">&gt;</span>max<span class="token punctuation">)</span><span class="token punctuation">{</span>
                max<span class="token operator">=</span>distance
                now<span class="token operator">=</span>pos
            <span class="token punctuation">}</span>
        <span class="token punctuation">}</span>
        
    <span class="token punctuation">}</span>

    <span class="token keyword">return</span> res
    
<span class="token punctuation">}</span><span class="token punctuation">;</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br><span class="line-number">15</span><br><span class="line-number">16</span><br><span class="line-number">17</span><br><span class="line-number">18</span><br><span class="line-number">19</span><br><span class="line-number">20</span><br><span class="line-number">21</span><br><span class="line-number">22</span><br><span class="line-number">23</span><br><span class="line-number">24</span><br><span class="line-number">25</span><br><span class="line-number">26</span><br><span class="line-number">27</span><br><span class="line-number">28</span><br><span class="line-number">29</span><br><span class="line-number">30</span><br><span class="line-number">31</span><br><span class="line-number">32</span><br><span class="line-number">33</span><br><span class="line-number">34</span><br><span class="line-number">35</span><br><span class="line-number">36</span><br></div></div><h3 id="_2-动态规划-一"><a href="#_2-动态规划-一" class="header-anchor">#</a> 2. 动态规划(一)</h3> <h4 id="_63-不同路径-ii-dfs-记忆化"><a href="#_63-不同路径-ii-dfs-记忆化" class="header-anchor">#</a> <a href="https://leetcode.cn/problems/unique-paths-ii/" target="_blank" rel="noopener noreferrer">63. 不同路径 II(dfs+记忆化)<span><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" x="0px" y="0px" viewBox="0 0 100 100" width="15" height="15" class="icon outbound"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path> <polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg> <span class="sr-only">(opens new window)</span></span></a></h4> <p>一个机器人位于一个 <code>m x n</code> 网格的左上角 （起始点在下图中标记为 “Start” ）。</p> <p>机器人每次只能向下或者向右移动一步。机器人试图达到网格的右下角（在下图中标记为 “Finish”）。</p> <p>现在考虑网格中有障碍物。那么从左上角到右下角将会有多少条不同的路径？</p> <p>网格中的障碍物和空位置分别用 <code>1</code> 和 <code>0</code> 来表示。</p> <p><strong>示例 1：</strong></p> <p><img src="https://assets.leetcode.com/uploads/2020/11/04/robot1.jpg" alt="img"></p> <div class="language- line-numbers-mode"><pre class="language-text"><code>输入：obstacleGrid = [[0,0,0],[0,1,0],[0,0,0]]
输出：2
解释：3x3 网格的正中间有一个障碍物。
从左上角到右下角一共有 2 条不同的路径：
1. 向右 -&gt; 向右 -&gt; 向下 -&gt; 向下
2. 向下 -&gt; 向下 -&gt; 向右 -&gt; 向右
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br></div></div><p><strong>示例 2：</strong></p> <p><img src="https://assets.leetcode.com/uploads/2020/11/04/robot2.jpg" alt="img"></p> <div class="language- line-numbers-mode"><pre class="language-text"><code>输入：obstacleGrid = [[0,1],[0,0]]
输出：1
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br></div></div><p><strong>提示：</strong></p> <ul><li><code>m == obstacleGrid.length</code></li> <li><code>n == obstacleGrid[i].length</code></li> <li><code>1 &lt;= m, n &lt;= 100</code></li> <li><code>obstacleGrid[i][j]</code> 为 <code>0</code> 或 <code>1</code></li></ul> <h5 id="解题思路-3"><a href="#解题思路-3" class="header-anchor">#</a> 解题思路</h5> <div class="language-shell line-numbers-mode"><pre class="language-shell"><code><span class="token number">1</span>. 遍历所有的状态空间，看每一个是否能到达终点
<span class="token number">2</span>.  在1基础上优化
<span class="token number">3</span>.   因为每一个点能否到达可以依赖其 右边和下边的点 
		是否能到达
<span class="token number">4</span>. 这些右方和下方的点计算过后，我们记录它是否能到达
	这样每个点只需要计算一次
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br></div></div><h5 id="完整代码-3"><a href="#完整代码-3" class="header-anchor">#</a> 完整代码</h5> <div class="language-js line-numbers-mode"><pre class="language-js"><code><span class="token comment">/**
 * @param {number[][]} obstacleGrid
 * @return {number}
 */</span>
<span class="token keyword">var</span> <span class="token function-variable function">uniquePathsWithObstacles</span> <span class="token operator">=</span> <span class="token keyword">function</span><span class="token punctuation">(</span><span class="token parameter">obstacleGrid</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>

    <span class="token comment">// 状态空间+记忆化搜索</span>

    <span class="token comment">// 我们遍历所有的网格，看其是否能到达终点</span>

    <span class="token keyword">let</span> dx<span class="token operator">=</span><span class="token punctuation">[</span><span class="token number">0</span><span class="token punctuation">,</span><span class="token number">1</span><span class="token punctuation">]</span>
    <span class="token keyword">let</span> dy<span class="token operator">=</span><span class="token punctuation">[</span><span class="token number">1</span><span class="token punctuation">,</span><span class="token number">0</span><span class="token punctuation">]</span>

    <span class="token keyword">let</span> m<span class="token operator">=</span>obstacleGrid<span class="token punctuation">.</span>length
    <span class="token keyword">let</span> n<span class="token operator">=</span>obstacleGrid<span class="token punctuation">[</span><span class="token number">0</span><span class="token punctuation">]</span><span class="token punctuation">.</span>length

    <span class="token keyword">let</span> myArr<span class="token operator">=</span><span class="token keyword">new</span> <span class="token class-name">Array</span><span class="token punctuation">(</span>m<span class="token punctuation">)</span>

    <span class="token keyword">for</span><span class="token punctuation">(</span><span class="token keyword">let</span> i<span class="token operator">=</span><span class="token number">0</span><span class="token punctuation">;</span>i<span class="token operator">&lt;</span>m<span class="token punctuation">;</span>i<span class="token operator">++</span><span class="token punctuation">)</span><span class="token punctuation">{</span>
        <span class="token keyword">let</span> arr<span class="token operator">=</span><span class="token keyword">new</span> <span class="token class-name">Array</span><span class="token punctuation">(</span>n<span class="token punctuation">)</span><span class="token punctuation">.</span><span class="token function">fill</span><span class="token punctuation">(</span><span class="token number">0</span><span class="token punctuation">)</span>
        myArr<span class="token punctuation">[</span>i<span class="token punctuation">]</span><span class="token operator">=</span>arr
    <span class="token punctuation">}</span>

    <span class="token comment">// console.log(valid)</span>

    <span class="token keyword">const</span> <span class="token function-variable function">dfs</span><span class="token operator">=</span><span class="token punctuation">(</span><span class="token parameter">x<span class="token punctuation">,</span>y</span><span class="token punctuation">)</span><span class="token operator">=&gt;</span><span class="token punctuation">{</span>
        <span class="token comment">// 越界</span>
        <span class="token keyword">if</span><span class="token punctuation">(</span>x<span class="token operator">&gt;=</span>m<span class="token operator">||</span>y<span class="token operator">&gt;=</span>n<span class="token operator">||</span>x<span class="token operator">&lt;</span><span class="token number">0</span><span class="token operator">||</span>y<span class="token operator">&lt;</span><span class="token number">0</span><span class="token punctuation">)</span><span class="token punctuation">{</span>
            <span class="token keyword">return</span> <span class="token number">0</span>
        <span class="token punctuation">}</span>
        <span class="token comment">// console.log(myArr)</span>
        <span class="token comment">// 有障碍物</span>
        <span class="token keyword">if</span><span class="token punctuation">(</span>obstacleGrid<span class="token punctuation">[</span>x<span class="token punctuation">]</span><span class="token punctuation">[</span>y<span class="token punctuation">]</span><span class="token punctuation">)</span><span class="token punctuation">{</span>
            <span class="token keyword">return</span> <span class="token number">0</span>
        <span class="token punctuation">}</span>
        <span class="token comment">// 到达终点</span>
        <span class="token keyword">if</span><span class="token punctuation">(</span>x<span class="token operator">===</span>m<span class="token operator">-</span><span class="token number">1</span><span class="token operator">&amp;&amp;</span>y<span class="token operator">===</span>n<span class="token operator">-</span><span class="token number">1</span><span class="token punctuation">)</span><span class="token punctuation">{</span>
            <span class="token keyword">return</span> <span class="token number">1</span>
        <span class="token punctuation">}</span>


		<span class="token comment">// 已经被计算过</span>
        <span class="token keyword">if</span><span class="token punctuation">(</span>myArr<span class="token punctuation">[</span>x<span class="token punctuation">]</span><span class="token punctuation">[</span>y<span class="token punctuation">]</span><span class="token operator">!==</span><span class="token number">0</span><span class="token punctuation">)</span><span class="token punctuation">{</span>
            <span class="token keyword">return</span> myArr<span class="token punctuation">[</span>x<span class="token punctuation">]</span><span class="token punctuation">[</span>y<span class="token punctuation">]</span>
        <span class="token punctuation">}</span>

        <span class="token comment">// 每个点考虑右方和下方的点能否到达</span>
        <span class="token keyword">for</span><span class="token punctuation">(</span><span class="token keyword">let</span> i<span class="token operator">=</span><span class="token number">0</span><span class="token punctuation">;</span>i<span class="token operator">&lt;</span><span class="token number">2</span><span class="token punctuation">;</span>i<span class="token operator">++</span><span class="token punctuation">)</span><span class="token punctuation">{</span>
            <span class="token keyword">let</span> nx<span class="token operator">=</span>x<span class="token operator">+</span>dx<span class="token punctuation">[</span>i<span class="token punctuation">]</span>
            <span class="token keyword">let</span> ny<span class="token operator">=</span>y<span class="token operator">+</span>dy<span class="token punctuation">[</span>i<span class="token punctuation">]</span>
            <span class="token comment">// console.log(nx,ny)</span>
            <span class="token comment">// console.log(x,y,myArr[0][0])</span>
            myArr<span class="token punctuation">[</span>x<span class="token punctuation">]</span><span class="token punctuation">[</span>y<span class="token punctuation">]</span><span class="token operator">+=</span><span class="token function">dfs</span><span class="token punctuation">(</span>nx<span class="token punctuation">,</span>ny<span class="token punctuation">)</span>
        <span class="token punctuation">}</span>

        <span class="token keyword">return</span> myArr<span class="token punctuation">[</span>x<span class="token punctuation">]</span><span class="token punctuation">[</span>y<span class="token punctuation">]</span>  
    <span class="token punctuation">}</span>

    <span class="token keyword">let</span> res<span class="token operator">=</span><span class="token function">dfs</span><span class="token punctuation">(</span><span class="token number">0</span><span class="token punctuation">,</span><span class="token number">0</span><span class="token punctuation">)</span>

    <span class="token comment">// console.log(myArr[0][0])</span>

    <span class="token keyword">return</span> res

    <span class="token comment">// console.log(valid[0][0])</span>

<span class="token punctuation">}</span><span class="token punctuation">;</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br><span class="line-number">15</span><br><span class="line-number">16</span><br><span class="line-number">17</span><br><span class="line-number">18</span><br><span class="line-number">19</span><br><span class="line-number">20</span><br><span class="line-number">21</span><br><span class="line-number">22</span><br><span class="line-number">23</span><br><span class="line-number">24</span><br><span class="line-number">25</span><br><span class="line-number">26</span><br><span class="line-number">27</span><br><span class="line-number">28</span><br><span class="line-number">29</span><br><span class="line-number">30</span><br><span class="line-number">31</span><br><span class="line-number">32</span><br><span class="line-number">33</span><br><span class="line-number">34</span><br><span class="line-number">35</span><br><span class="line-number">36</span><br><span class="line-number">37</span><br><span class="line-number">38</span><br><span class="line-number">39</span><br><span class="line-number">40</span><br><span class="line-number">41</span><br><span class="line-number">42</span><br><span class="line-number">43</span><br><span class="line-number">44</span><br><span class="line-number">45</span><br><span class="line-number">46</span><br><span class="line-number">47</span><br><span class="line-number">48</span><br><span class="line-number">49</span><br><span class="line-number">50</span><br><span class="line-number">51</span><br><span class="line-number">52</span><br><span class="line-number">53</span><br><span class="line-number">54</span><br><span class="line-number">55</span><br><span class="line-number">56</span><br><span class="line-number">57</span><br><span class="line-number">58</span><br><span class="line-number">59</span><br><span class="line-number">60</span><br><span class="line-number">61</span><br><span class="line-number">62</span><br><span class="line-number">63</span><br><span class="line-number">64</span><br><span class="line-number">65</span><br><span class="line-number">66</span><br><span class="line-number">67</span><br></div></div></div></div>  <div class="page-edit"><div class="edit-link"><a href="https://github.com/linxin1123/vuepress-blog/edit/master/docs/07.算法/41.算法训练营/14.动态规划(一).md" target="_blank" rel="noopener noreferrer">编辑</a> <span><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" x="0px" y="0px" viewBox="0 0 100 100" width="15" height="15" class="icon outbound"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path> <polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg> <span class="sr-only">(opens new window)</span></span></div> <!----> <div class="last-updated"><span class="prefix">上次更新:</span> <span class="time">2023/02/17, 11:29:32</span></div></div> <div class="page-nav-wapper"><div class="page-nav-centre-wrap"><a href="/pages/0e21af/" class="page-nav-centre page-nav-centre-prev"><div class="tooltip">深度-广度搜索-状态空间-cnblog</div></a> <a href="/pages/832d5e/" class="page-nav-centre page-nav-centre-next"><div class="tooltip">排序</div></a></div> <div class="page-nav"><p class="inner"><span class="prev">
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